Web accessibility technology at the IBM Tokyo Research Laboratory

IBM Journal of Research and Development, Sep-Nov 2004 by Maeda, J, Fukuda, K, Takagi, H, Asakawa, C

This paper provides an overview of Web accessibility technologies developed at the IBM Tokyo Research Laboratory. Home Page Reader provides an easy and comfortable way for the blind to read Web pages. Transcoding technology solves problems that arise when a voice browser, such as Home Page Reader, reads Web pages. It also offers more comfortable ways for visually impaired people and senior citizens to read Web pages. Accessibility Designer, the main focus of this paper, allows page designers to learn about disabilities and to create more accessible and usable Web pages at authoring time. It has two modes: a low-vision mode and a blind mode. The low-vision mode simulates the perception of people with low vision and detects inaccessible parts in the target page. The blind mode visualizes the usability of a voice browser for the target page and detects accessibility and usability problems. Accessibility Observer makes it easier for Web developers to detect accessibility problems.

Introduction

Research activity on accessibility at the IBM Tokyo Research Laboratory (TRL) started in 1985. Accessibility means access to information for all-focusing on people with disabilities and senior citizens. Ensuring accessibility improves the quality of life for such people by removing barriers that prevent them from taking part in many important life activities.

The history of our accessibility research began with studies on digital Braille for the blind. To solve problems with Braille punched into paper, the Braille editing system [1], the Braille information network [2], and the Braille dictionary system were developed.

In the mid-1990s, the use of the Internet became popular, and the World Wide Web became an essential information resource for our society. Today, huge amounts of information can be obtained through the Web, and the Web permeates our social activities.

As this environment developed, we shifted our focus, in 1996, to Internet accessibility technologies to enable people with disabilities to enjoy the enormous benefit of the Internet. The first success was achieved in 1997 with Home Page Reader [3], described in the next section. It provided an easy and comfortable way for the blind to read Web pages. Since then, we have been doing research mainly on the Web, extending our targets for content that can be made accessible and for applications to which we can apply our technologies in accordance with changes in the social and technical environments. Furthermore, in the last several years, our research area has been expanded; in addition to accessibility, we added usability. We have also expanded our target user group from the blind to also include people with low vision. For the purposes of this paper, we use the term low-vision people as a generic term for people who have weakened vision-such as people with amblyopia or color blindness, and senior citizens with age-weakened eyesight-but who are still able to read Web pages.

In this paper, we focus on three changes in the environment:

1. Evolution of Web content: In the early stages of the Web, pages were simple, and most of their content was text that could easily be read by Home Page Reader. As the Web evolves, however, Web pages are gradually becoming more complicated, and their content has more and more visual elements, such as images, that can often cause accessibility problems. In addition, most business sites have recently begun providing Web pages dynamically on demand by using new server-side technologies, such as JavaServer** Pages (JSP**) and servlets. These technologies make it more difficult to improve the accessibility of pages using conventional accessibility tools.

2. Necessity of author-side technologies: Accessibility technologies are not only for senior citizens and people with disabilities. Changes in social and business environments, such as the enactment in the United States of Section 508 of the Rehabilitation Act Amendment, call for site owners and page designers to make their Web pages accessible.

3. Usability: Usability means ease of use. Ensuring usability is necessary for comfortable Web access. There exist several standardized accessibility guidelines, such as the World Wide Web Consortium (W3C**) Web Content Accessibility Guidelines (WCAG) [4], Section 508 [5], and IBM Corporate Instruction 162 [6]. They describe certain levels of accessibility. However, Web pages complying with these guidelines are not always easy to read. For example, most of the accessibility guidelines require that page designers provide an ALT attribute for each of the images. This provides an alternate text description of the image for user agents that cannot display images. However, providing an inappropriate ALT attribute makes the situation worse, not better.

This paper provides an overview of Web accessibility technologies invented and developed at TRL. The next section discusses Home Page Reader for the blind, followed by a section describing accessibility issues. After that, we illustrate transcoding technology to address accessibility issues of already-existing Web pages. We then demonstrate Accessibility Designer, which is the main focus of this paper. Accessibility Designer helps Web designers and developers ensure both the usability of Web pages and their accessibility. It is characterized by providing low-vision simulation and blind usability visualization features. The following section presents the server-side Java** Observer (Accessibility Observer) for improving the accessibility and usability of dynamically produced Web pages, and the final section concludes the paper.